Finite Element Analysis of Defective Induction Motor

This dissertation provides a methodology for the computation of flux distribution in defective induction machines. Having obtained the flux distribution for the applied voltage, the stator current in each phase for any load can be calculated, and hence it can be determined if continuation of the operation of the defective machine under the applied load is safe. The methodology is based on the use of Maxwell's equations to derive a unified equation. This equation relates the space and time derivatives of the magnetic vector potential (MVP) of each point within the machine to the density of the applied current at the point. Applying the method of finite elements to this equation at different sections of the machine leads to a global equation. In this derivation, saturation at any point of the machine and at any instant of time is fully accounted for. The global equation is a set of nonlinear time domain differential equations. A step-by-step numerical method is employed to integrate this global equation. This process yields the value of MVP for any point of the machine at any instant of time. The computer program developed in this work to carry out the above tasks is validated by applying it to simple electromagnetic systems. It is then used to produce MVP contours of an induction machine for three defects. Advisors/Committee Members: Jaleeli, Nasser.